zoj 1895 Pairsumonious Numbers

zoj 1895 Pairsumonious Numbers

#include<set>#include<iostream>#include<cstring>#include<cstdlib>#include<stdio.h>#include<algorithm>using namespace std;int N,S;int result[50];int part[12];void fun(){int i,j,k,flag,t;    multiset<int> sum;    multiset<int>::iterator iter;    for(i=2;i<S;i++){sum.insert(result[i]);}for(i=2;i<S;i++){part[0] = (result[0] + result[1] - result[i])/2;part[1] = result[0] - part[0];part[2] = result[i] - part[1];if(part[0] > part[1] || part[1] > part[2])continue;multiset<int> s = sum;iter = s.find(result[i]);s.erase(iter);j = 3;flag = 0;while(j < N){iter = s.begin();part[j] = *iter - part[0];for(k=0;k<j;k++){if(part[j] < part[k]){flag = 1;break;}t = part[j] + part[k];iter = s.find(t);if(iter == s.end()){flag = 1;break;} else {s.erase(iter);}}j ++;}if(flag ==0 && s.size() ==0){cout<<part[0];for(i=1;i<N;i++){cout<<" "<<part[i];}cout<<endl;return ;}}cout<<"Impossible"<<endl;}int main(){    int i;       while(cin>>N){S = N * (N-1) /2;for(i=0;i<S;i++){cin>>result[i];}sort(result, result + S);fun();}    return 0;}